get number of files in a directory and its subdirectories

Question

using this code

new File(\"/mnt/sdcard/folder\").listFiles().length

returns a sum of folders and files in a particular directory without ca

Answer 1

Just for the record, you may also use iteration instead of recursion:

public static int countFiles(final File dir) {
    final ArrayDeque dirs = new ArrayDeque<>();
    dirs.add(dir);
    int cnt = 0;
    while (!dirs.isEmpty()) {
        final File[] files = dirs.poll().listFiles();
        for (final File f: files)
            if (f.isDirectory())
                dirs.add(f);
            else
                ++cnt;
    }
    return cnt;
}

In this implementation I'm using ArrayDeque but you can use any Queue or any List for the job.